A member of the national Coronavirus Combat Taskforce of Iran on Saturday said based on random serologic test findings 20 percent of Iranians must have had been infected with the coronavirus so far.
"This test is done to find out what percentage of the population in an area have been infected with the coronavirus. Random tests we carried out has shown that the virus has infected 18 million Iranians, that is 20 percent of the population," Dr. Masoud Mardani was quoted by the Iranian Students News Agency (ISNA) as saying.
The estimated number resulting from random serologic tests is 75 times more than the official number of cases since February which is nearly 238,000.
According to the latest official announcement on Saturday, Iran's total death toll has now reached 11,408 with 148 more deaths since Friday.
Serologic tests are blood tests that look for antibodies – proteins (antibodies) made by the immune system to destroy viruses, bacteria, etc. -- in blood. They can involve a number of laboratory techniques. Antibody test results are especially important for detecting previous infections in people who had few or no symptoms.
Different types of serologic tests are used to diagnose various disease conditions. Serologic tests are now extensively used to help estimate how many people in a certain country have been affected with SARS-CoV-2, the virus that causes COVID-19. For COVID-19 the tests look for immunoglobins (IgG), the most common antibody which is present in the blood of those with bacterial and viral infections.
It is yet not clear if the antibodies that the human body makes to fight SARS-CoV-2 will provide immunity from being infected again or if it does, how long the immunity will last. Extensive research is underway in different countries on the subject.
Health authorities are very concerned about the spike in the number of new cases and deaths in the past three weeks. From July 5 wearing masks will be compulsory in all public places. Health officials, however, say most of the new patients have been infected at gatherings of families and friends including weddings and funerals.